[4/9] iomap: move the SEEK_HOLE code into a separate file
diff mbox series

Message ID 156321358581.148361.8774330141606166898.stgit@magnolia
State New
Headers show
Series
  • iomap: regroup code by functional area
Related show

Commit Message

Darrick J. Wong July 15, 2019, 5:59 p.m. UTC
From: Darrick J. Wong <darrick.wong@oracle.com>

Move the SEEK_HOLE/SEEK_DATA code into a separate file so that we can
group related functions in a single file instead of having a single
enormous source file.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
 fs/iomap.c        |  201 --------------------------------------------------
 fs/iomap/Makefile |    3 -
 fs/iomap/seek.c   |  214 +++++++++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 216 insertions(+), 202 deletions(-)
 create mode 100644 fs/iomap/seek.c

Comments

Christoph Hellwig July 17, 2019, 5:01 a.m. UTC | #1
> diff --git a/fs/iomap/seek.c b/fs/iomap/seek.c
> new file mode 100644
> index 000000000000..0c36bef46522
> --- /dev/null
> +++ b/fs/iomap/seek.c
> @@ -0,0 +1,214 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright (C) 2010 Red Hat, Inc.
> + * Copyright (c) 2016-2018 Christoph Hellwig.
> + */

This looks a little odd.  There is nothing in here from Daves original
iomap prototype.  It did start out with code from Andreas though which
might or might not be RH copyright.  So we'll need Andreas and/or RH
legal to chime in.

Otherwise looks good:

Reviewed-by: Christoph Hellwig <hch@lst.de>
Andreas Gruenbacher July 17, 2019, 12:44 p.m. UTC | #2
On Wed, 17 Jul 2019 at 07:01, Christoph Hellwig <hch@infradead.org> wrote:
> > diff --git a/fs/iomap/seek.c b/fs/iomap/seek.c
> > new file mode 100644
> > index 000000000000..0c36bef46522
> > --- /dev/null
> > +++ b/fs/iomap/seek.c
> > @@ -0,0 +1,214 @@
> > +// SPDX-License-Identifier: GPL-2.0
> > +/*
> > + * Copyright (C) 2010 Red Hat, Inc.
> > + * Copyright (c) 2016-2018 Christoph Hellwig.
> > + */
>
> This looks a little odd.  There is nothing in here from Daves original
> iomap prototype.  It did start out with code from Andreas though which
> might or might not be RH copyright.  So we'll need Andreas and/or RH
> legal to chime in.

That code should be Copyright (C) 2017 Red Hat, Inc.

> Otherwise looks good:
>
> Reviewed-by: Christoph Hellwig <hch@lst.de>

Thanks,
Andreas
Darrick J. Wong July 17, 2019, 2:53 p.m. UTC | #3
On Wed, Jul 17, 2019 at 02:44:20PM +0200, Andreas Gruenbacher wrote:
> On Wed, 17 Jul 2019 at 07:01, Christoph Hellwig <hch@infradead.org> wrote:
> > > diff --git a/fs/iomap/seek.c b/fs/iomap/seek.c
> > > new file mode 100644
> > > index 000000000000..0c36bef46522
> > > --- /dev/null
> > > +++ b/fs/iomap/seek.c
> > > @@ -0,0 +1,214 @@
> > > +// SPDX-License-Identifier: GPL-2.0
> > > +/*
> > > + * Copyright (C) 2010 Red Hat, Inc.
> > > + * Copyright (c) 2016-2018 Christoph Hellwig.
> > > + */
> >
> > This looks a little odd.  There is nothing in here from Daves original
> > iomap prototype.  It did start out with code from Andreas though which
> > might or might not be RH copyright.  So we'll need Andreas and/or RH
> > legal to chime in.
> 
> That code should be Copyright (C) 2017 Red Hat, Inc.

Ok, fixed.

--D

> > Otherwise looks good:
> >
> > Reviewed-by: Christoph Hellwig <hch@lst.de>
> 
> Thanks,
> Andreas

Patch
diff mbox series

diff --git a/fs/iomap.c b/fs/iomap.c
index d14d75a97ab3..ad994c408cb8 100644
--- a/fs/iomap.c
+++ b/fs/iomap.c
@@ -1149,207 +1149,6 @@  vm_fault_t iomap_page_mkwrite(struct vm_fault *vmf, const struct iomap_ops *ops)
 }
 EXPORT_SYMBOL_GPL(iomap_page_mkwrite);
 
-/*
- * Seek for SEEK_DATA / SEEK_HOLE within @page, starting at @lastoff.
- * Returns true if found and updates @lastoff to the offset in file.
- */
-static bool
-page_seek_hole_data(struct inode *inode, struct page *page, loff_t *lastoff,
-		int whence)
-{
-	const struct address_space_operations *ops = inode->i_mapping->a_ops;
-	unsigned int bsize = i_blocksize(inode), off;
-	bool seek_data = whence == SEEK_DATA;
-	loff_t poff = page_offset(page);
-
-	if (WARN_ON_ONCE(*lastoff >= poff + PAGE_SIZE))
-		return false;
-
-	if (*lastoff < poff) {
-		/*
-		 * Last offset smaller than the start of the page means we found
-		 * a hole:
-		 */
-		if (whence == SEEK_HOLE)
-			return true;
-		*lastoff = poff;
-	}
-
-	/*
-	 * Just check the page unless we can and should check block ranges:
-	 */
-	if (bsize == PAGE_SIZE || !ops->is_partially_uptodate)
-		return PageUptodate(page) == seek_data;
-
-	lock_page(page);
-	if (unlikely(page->mapping != inode->i_mapping))
-		goto out_unlock_not_found;
-
-	for (off = 0; off < PAGE_SIZE; off += bsize) {
-		if (offset_in_page(*lastoff) >= off + bsize)
-			continue;
-		if (ops->is_partially_uptodate(page, off, bsize) == seek_data) {
-			unlock_page(page);
-			return true;
-		}
-		*lastoff = poff + off + bsize;
-	}
-
-out_unlock_not_found:
-	unlock_page(page);
-	return false;
-}
-
-/*
- * Seek for SEEK_DATA / SEEK_HOLE in the page cache.
- *
- * Within unwritten extents, the page cache determines which parts are holes
- * and which are data: uptodate buffer heads count as data; everything else
- * counts as a hole.
- *
- * Returns the resulting offset on successs, and -ENOENT otherwise.
- */
-static loff_t
-page_cache_seek_hole_data(struct inode *inode, loff_t offset, loff_t length,
-		int whence)
-{
-	pgoff_t index = offset >> PAGE_SHIFT;
-	pgoff_t end = DIV_ROUND_UP(offset + length, PAGE_SIZE);
-	loff_t lastoff = offset;
-	struct pagevec pvec;
-
-	if (length <= 0)
-		return -ENOENT;
-
-	pagevec_init(&pvec);
-
-	do {
-		unsigned nr_pages, i;
-
-		nr_pages = pagevec_lookup_range(&pvec, inode->i_mapping, &index,
-						end - 1);
-		if (nr_pages == 0)
-			break;
-
-		for (i = 0; i < nr_pages; i++) {
-			struct page *page = pvec.pages[i];
-
-			if (page_seek_hole_data(inode, page, &lastoff, whence))
-				goto check_range;
-			lastoff = page_offset(page) + PAGE_SIZE;
-		}
-		pagevec_release(&pvec);
-	} while (index < end);
-
-	/* When no page at lastoff and we are not done, we found a hole. */
-	if (whence != SEEK_HOLE)
-		goto not_found;
-
-check_range:
-	if (lastoff < offset + length)
-		goto out;
-not_found:
-	lastoff = -ENOENT;
-out:
-	pagevec_release(&pvec);
-	return lastoff;
-}
-
-
-static loff_t
-iomap_seek_hole_actor(struct inode *inode, loff_t offset, loff_t length,
-		      void *data, struct iomap *iomap)
-{
-	switch (iomap->type) {
-	case IOMAP_UNWRITTEN:
-		offset = page_cache_seek_hole_data(inode, offset, length,
-						   SEEK_HOLE);
-		if (offset < 0)
-			return length;
-		/* fall through */
-	case IOMAP_HOLE:
-		*(loff_t *)data = offset;
-		return 0;
-	default:
-		return length;
-	}
-}
-
-loff_t
-iomap_seek_hole(struct inode *inode, loff_t offset, const struct iomap_ops *ops)
-{
-	loff_t size = i_size_read(inode);
-	loff_t length = size - offset;
-	loff_t ret;
-
-	/* Nothing to be found before or beyond the end of the file. */
-	if (offset < 0 || offset >= size)
-		return -ENXIO;
-
-	while (length > 0) {
-		ret = iomap_apply(inode, offset, length, IOMAP_REPORT, ops,
-				  &offset, iomap_seek_hole_actor);
-		if (ret < 0)
-			return ret;
-		if (ret == 0)
-			break;
-
-		offset += ret;
-		length -= ret;
-	}
-
-	return offset;
-}
-EXPORT_SYMBOL_GPL(iomap_seek_hole);
-
-static loff_t
-iomap_seek_data_actor(struct inode *inode, loff_t offset, loff_t length,
-		      void *data, struct iomap *iomap)
-{
-	switch (iomap->type) {
-	case IOMAP_HOLE:
-		return length;
-	case IOMAP_UNWRITTEN:
-		offset = page_cache_seek_hole_data(inode, offset, length,
-						   SEEK_DATA);
-		if (offset < 0)
-			return length;
-		/*FALLTHRU*/
-	default:
-		*(loff_t *)data = offset;
-		return 0;
-	}
-}
-
-loff_t
-iomap_seek_data(struct inode *inode, loff_t offset, const struct iomap_ops *ops)
-{
-	loff_t size = i_size_read(inode);
-	loff_t length = size - offset;
-	loff_t ret;
-
-	/* Nothing to be found before or beyond the end of the file. */
-	if (offset < 0 || offset >= size)
-		return -ENXIO;
-
-	while (length > 0) {
-		ret = iomap_apply(inode, offset, length, IOMAP_REPORT, ops,
-				  &offset, iomap_seek_data_actor);
-		if (ret < 0)
-			return ret;
-		if (ret == 0)
-			break;
-
-		offset += ret;
-		length -= ret;
-	}
-
-	if (length <= 0)
-		return -ENXIO;
-	return offset;
-}
-EXPORT_SYMBOL_GPL(iomap_seek_data);
-
 /*
  * Private flags for iomap_dio, must not overlap with the public ones in
  * iomap.h:
diff --git a/fs/iomap/Makefile b/fs/iomap/Makefile
index 861c07137792..12dc7f844bbd 100644
--- a/fs/iomap/Makefile
+++ b/fs/iomap/Makefile
@@ -9,6 +9,7 @@  ccflags-y += -I $(srctree)/$(src)/..
 obj-$(CONFIG_FS_IOMAP)		+= iomap.o
 
 iomap-y				+= \
-					fiemap.o
+					fiemap.o \
+					seek.o
 
 iomap-$(CONFIG_SWAP)		+= swapfile.o
diff --git a/fs/iomap/seek.c b/fs/iomap/seek.c
new file mode 100644
index 000000000000..0c36bef46522
--- /dev/null
+++ b/fs/iomap/seek.c
@@ -0,0 +1,214 @@ 
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2010 Red Hat, Inc.
+ * Copyright (c) 2016-2018 Christoph Hellwig.
+ */
+#include <linux/module.h>
+#include <linux/compiler.h>
+#include <linux/fs.h>
+#include <linux/iomap.h>
+#include <linux/pagemap.h>
+#include <linux/pagevec.h>
+
+#include "internal.h"
+
+/*
+ * Seek for SEEK_DATA / SEEK_HOLE within @page, starting at @lastoff.
+ * Returns true if found and updates @lastoff to the offset in file.
+ */
+static bool
+page_seek_hole_data(struct inode *inode, struct page *page, loff_t *lastoff,
+		int whence)
+{
+	const struct address_space_operations *ops = inode->i_mapping->a_ops;
+	unsigned int bsize = i_blocksize(inode), off;
+	bool seek_data = whence == SEEK_DATA;
+	loff_t poff = page_offset(page);
+
+	if (WARN_ON_ONCE(*lastoff >= poff + PAGE_SIZE))
+		return false;
+
+	if (*lastoff < poff) {
+		/*
+		 * Last offset smaller than the start of the page means we found
+		 * a hole:
+		 */
+		if (whence == SEEK_HOLE)
+			return true;
+		*lastoff = poff;
+	}
+
+	/*
+	 * Just check the page unless we can and should check block ranges:
+	 */
+	if (bsize == PAGE_SIZE || !ops->is_partially_uptodate)
+		return PageUptodate(page) == seek_data;
+
+	lock_page(page);
+	if (unlikely(page->mapping != inode->i_mapping))
+		goto out_unlock_not_found;
+
+	for (off = 0; off < PAGE_SIZE; off += bsize) {
+		if (offset_in_page(*lastoff) >= off + bsize)
+			continue;
+		if (ops->is_partially_uptodate(page, off, bsize) == seek_data) {
+			unlock_page(page);
+			return true;
+		}
+		*lastoff = poff + off + bsize;
+	}
+
+out_unlock_not_found:
+	unlock_page(page);
+	return false;
+}
+
+/*
+ * Seek for SEEK_DATA / SEEK_HOLE in the page cache.
+ *
+ * Within unwritten extents, the page cache determines which parts are holes
+ * and which are data: uptodate buffer heads count as data; everything else
+ * counts as a hole.
+ *
+ * Returns the resulting offset on successs, and -ENOENT otherwise.
+ */
+static loff_t
+page_cache_seek_hole_data(struct inode *inode, loff_t offset, loff_t length,
+		int whence)
+{
+	pgoff_t index = offset >> PAGE_SHIFT;
+	pgoff_t end = DIV_ROUND_UP(offset + length, PAGE_SIZE);
+	loff_t lastoff = offset;
+	struct pagevec pvec;
+
+	if (length <= 0)
+		return -ENOENT;
+
+	pagevec_init(&pvec);
+
+	do {
+		unsigned nr_pages, i;
+
+		nr_pages = pagevec_lookup_range(&pvec, inode->i_mapping, &index,
+						end - 1);
+		if (nr_pages == 0)
+			break;
+
+		for (i = 0; i < nr_pages; i++) {
+			struct page *page = pvec.pages[i];
+
+			if (page_seek_hole_data(inode, page, &lastoff, whence))
+				goto check_range;
+			lastoff = page_offset(page) + PAGE_SIZE;
+		}
+		pagevec_release(&pvec);
+	} while (index < end);
+
+	/* When no page at lastoff and we are not done, we found a hole. */
+	if (whence != SEEK_HOLE)
+		goto not_found;
+
+check_range:
+	if (lastoff < offset + length)
+		goto out;
+not_found:
+	lastoff = -ENOENT;
+out:
+	pagevec_release(&pvec);
+	return lastoff;
+}
+
+
+static loff_t
+iomap_seek_hole_actor(struct inode *inode, loff_t offset, loff_t length,
+		      void *data, struct iomap *iomap)
+{
+	switch (iomap->type) {
+	case IOMAP_UNWRITTEN:
+		offset = page_cache_seek_hole_data(inode, offset, length,
+						   SEEK_HOLE);
+		if (offset < 0)
+			return length;
+		/* fall through */
+	case IOMAP_HOLE:
+		*(loff_t *)data = offset;
+		return 0;
+	default:
+		return length;
+	}
+}
+
+loff_t
+iomap_seek_hole(struct inode *inode, loff_t offset, const struct iomap_ops *ops)
+{
+	loff_t size = i_size_read(inode);
+	loff_t length = size - offset;
+	loff_t ret;
+
+	/* Nothing to be found before or beyond the end of the file. */
+	if (offset < 0 || offset >= size)
+		return -ENXIO;
+
+	while (length > 0) {
+		ret = iomap_apply(inode, offset, length, IOMAP_REPORT, ops,
+				  &offset, iomap_seek_hole_actor);
+		if (ret < 0)
+			return ret;
+		if (ret == 0)
+			break;
+
+		offset += ret;
+		length -= ret;
+	}
+
+	return offset;
+}
+EXPORT_SYMBOL_GPL(iomap_seek_hole);
+
+static loff_t
+iomap_seek_data_actor(struct inode *inode, loff_t offset, loff_t length,
+		      void *data, struct iomap *iomap)
+{
+	switch (iomap->type) {
+	case IOMAP_HOLE:
+		return length;
+	case IOMAP_UNWRITTEN:
+		offset = page_cache_seek_hole_data(inode, offset, length,
+						   SEEK_DATA);
+		if (offset < 0)
+			return length;
+		/*FALLTHRU*/
+	default:
+		*(loff_t *)data = offset;
+		return 0;
+	}
+}
+
+loff_t
+iomap_seek_data(struct inode *inode, loff_t offset, const struct iomap_ops *ops)
+{
+	loff_t size = i_size_read(inode);
+	loff_t length = size - offset;
+	loff_t ret;
+
+	/* Nothing to be found before or beyond the end of the file. */
+	if (offset < 0 || offset >= size)
+		return -ENXIO;
+
+	while (length > 0) {
+		ret = iomap_apply(inode, offset, length, IOMAP_REPORT, ops,
+				  &offset, iomap_seek_data_actor);
+		if (ret < 0)
+			return ret;
+		if (ret == 0)
+			break;
+
+		offset += ret;
+		length -= ret;
+	}
+
+	if (length <= 0)
+		return -ENXIO;
+	return offset;
+}
+EXPORT_SYMBOL_GPL(iomap_seek_data);